1. 1 LHCb CALO commissioning meeting 19.05.08 Anatoli Konoplyannikov /ITEP/ XCAL commissioning with LED Outline Scan data collected on HCAL and ECAL during the last week; Test of the HV stabilization time for HCAL and ECAL Data collection problems LEDTSB configuration problem and correction of the LED – FE boards CALO DB connectivity Planning

2. 2 LHCb CALO commissioning meeting 19.05.08 Anatoli Konoplyannikov /ITEP/ XCAL commissioning with LED Description of the collected data All LED scan data are collected with Calibration trigger with a rate of 56 Hz and 5(TAE) sequence of L0s. Basic LED timing Scan Data collection 17.05.08 ECAL-C: ECAL data (800 ev/step, zigzag 1/8 freq, steps=13, tot_ev= 10400): 1. /daqarea/lhcb/data/2008/RAW/ECAL/PHYSICS|TimeScan/023035 HV = nominal, LEDTSB_del=150 ns; LED_intens=nominal cnt; FErecipe-Default ECAL-C data (Trigger rate=56 HZ; 400 ev/step, zigzag 1/8 freq, steps=250, tot_ev= 95610): But ROOT file includes only 60K events, due to the DAQ was crashed. 2. /daqarea/lhcb/data/2008/RAW/ECAL/PHYSICS|TimeScan/023036 HV = nominal, LEDTSB_del=150 ns; LED_intens=nominal;FErecipe-Default, collection time=48:20 min After 5 steps HV goes from STANDBY1 (was set 1hour before) to Nominal HV Data collection 15.05.08 HCAL-C: HCAL data (Trigger rate=56 HZ; 400 ev/step, zigzag 1/8 freq, steps=200, tot_ev= 78408): 1. /daqarea/lhcb/data/2008/RAW/HCAL/PHYSICS|TimeScan/022984 HV = nominal, LEDTSB_del=150 ns; LED_intens=2000 cnt;FErecipe-Default, collection time=37:05 min After 5 steps HV goes from STANDBY1 (was set 1hour before) to Nominal HV

3. 3 LHCb CALO commissioning meeting 19.05.08 Anatoli Konoplyannikov /ITEP/ XCAL commissioning with LED Test of the HV stabilization time for HCAL-C and ECAL-C Time (min) ADC (cnt) Time (min) HCAL module 5 ADC response vs time after HV ON. ECAL ADC response vs time after HV ON. 1 hour STANDBY nominal HV 16 Channels Raw data examples.

4. 4 LHCb CALO commissioning meeting 19.05.08 Anatoli Konoplyannikov /ITEP/ XCAL commissioning with LED Test of the HV stabilization time for HCAL - C Time (min) 1 % Stabilizing Time of about 15 min HCAL module 5 normalized ADC response vs time after HV ON. HCAL normalized PIN ADC response vs time after HV ON. 16 PIN Channels 16 Channels

5. 5 LHCb CALO commissioning meeting 19.05.08 Anatoli Konoplyannikov /ITEP/ XCAL commissioning with LED Test of the HV stabilization time for HCAL - C Distributions of the HCAL-C PMT gain drop after changing HV from state STANDBY to READY Number of PMTs with a Gain drop (%) during all 35 min Number of PMTs with a Gain drop (%) during last 20 min Gain Drop ( % ) +- 1 %

6. 6 LHCb CALO commissioning meeting 19.05.08 Anatoli Konoplyannikov /ITEP/ XCAL commissioning with LED Data collection problems  losing events during a few steps  adding a wrong data (~ 2000 cnt) during a data collection N events Expected N events = 80 000, Collected N events = 78408. HCAL-C data file 22984 ECAL-C data file 23036

7. 7 LHCb CALO commissioning meeting 12.05.08 Anatoli Konoplyannikov /ITEP/ XCAL commissioning with LEDBasic LED timing Scan 67 130009 1200 C117 3 110009 34436 34500 34564 34628 34438 34502 34566 34630 34439 34503 34567 34631 34437 34501 34565 34629 80816 80817 80818 80819 80824 80825 80826 80827 80828 80829 80830 80831 80820 80821 80822 80823 8_08_16 8_08_17 8_08_18 8_08_19 ECAL - C 16 channel PMT group raw scan data plots. The readout channels of this LED group are in crate 8 and slot 8. The group is illuminated by one LED (N_67) in the same time, but scanned plots for a few channels have a wrong shapes. PMT group connectivity shows the addresses of LEDTSB, LED_DAC, PIN_ADC, Cell, FE board After LEDTSB recalibration

8. 8 LHCb CALO commissioning meeting 19.05.08 Anatoli Konoplyannikov /ITEP/ XCAL commissioning with LEDBasic LED timing Scan The reason of this behavior is understood. There were two simultaneous errors: First is the real LED fibers to PMT connections are different from the CALO data base. It means that four channels on the first plot are illuminated by other LED. Channel connectivity for board 8 of crate 8 is shown on previous slide. Second is one LEDTSB output that triggering LED pulses is wrongly calibrated and as you can see we have swapped by about 12.5 ns time intervals.

9. 9 LHCb CALO commissioning meeting 12.05.08 Anatoli Konoplyannikov /ITEP/ XCAL commissioning with LED Basic LED timing Scan Conclusions & Planning.  The LED scan data could be collected with main DAQ now, but we still have some problems with data quality;  The test of the PMT stabilization time after HV switched ON has been done with ECAL and HCAL. The stabilization time is about 15 min;  The problem with LED to FE boards connectivity was found and an additional scan test will be developed;  Some times the LEDTSB initialization with ECS is not completely correct. An additional study will be done for improving this.